The Battle of Zelinin was a battle that took place during the Five Year War, between the Bosmer and the Khajiit. During this war, the Khajiit had hired Nords as advisors. The Nords insisted upon the Khajiit wearing plate mail (Heavy Armor) during this battle. As a result of this, the Khajiit were heavily restricted in their movements, and consequently, they were slaughtered by the more agile Bosmer.
Because of their new understanding of the restrictions of this armor type, the Elsweyr generals decided from this time onward to use Medium Armor instead. This lighter armor was utilized to great effect during the Heart of Anequina battle. Eventually, they would win the battle.